Control for air conditioning apparatus



Jan..3, 1939. w.w. TIAMIVVIIS 2,142,423

CONTROL FOR AIR CONDITIONING APPARATUS Filed Sept. 4, 1936 ,3; INVENTOR.J

William, iVaZfer .Yiz'rrzrrzzis Patented Jan. 3, 1939 UNITED S A EPATENT OFFICE 'coN'raor. FOR An CONDITIONING.

. 'Arrm'ms William Walter Timmis, Glen Cove, N. Y., assignor to AmericanRadiator- Company, New York, N. Y., a corporation of New JerseyApplication Sept'ember 4, 1 a3s, sen i No. 99,367- 1 cmmi (01. 236-44.)

' ating several air conditioning instrumentalities employed in thesystem will be under manual control for controlling the operation of oneor more of said instrumentalities.

' Further, said invention has for its object to provide a system of thecharacter specified in which the air circulating means thereof may beoperated either conjointly with a humidifying means thereof "orindependently thereof.

Further, said invention has for its object to provide a system of thecharacter specified in which the air circulating means and thehumidifying means thereof, or the air circulating means alone, may beoperated either under control of a temperature responsive device or not,as required.

Other objects will in part be obvious and in part be pointed outhereinafter.

in the accompanying drawing, Figure l is a vertical, diagrammaticsection of one form of system constructed according to and embodying mysaid/ invention, and

.Fig. 2, is a wiring diagram thereof.

Referring to the drawing, the unit I of the particular air conditioningsystem disclosed, is of the type supplementing the usual heating systememployed in a house or, building, and includes an outer casing ll havinga return portion or duct l2 from the room orrooms of the buildinmandalso in communication with the fresh air from the outside of thebuilding. The air delivered through the portion l2 to the unit In firstpasses through a suitable filter [3, preferably composed of corrugatedfibre board arranged to form V-shaped cellular passages for causingabrupt change in the direction of travel of the air. The surfaces of thefibre board are coated with a tacky compound for catching dust, soot,pollen,

etc., carried by the air.

The air is forced or drawn through the casing II and into the supplypipe oroutlet H for delivery to the room or rooms by air circulatingmeans is, preferably comprising a centrifugaltype of blower driven by anelectric motor [6. The blower I5 .is preferably located within an innercasing l5, while the motor I6 is mounted within the casing ll below thesupply outlet I.

An air heating element I1 is located within the casing I lbetween theblower casing-iii and a'second inner casing l8 forming a humidifying orspray chamber 19 immediately in advance. of the filter l3. The heatingmeans l'l preferably comprises the cast-iron headers 20 communicatingwith each other through the usual intervening heat radiating member madeup of tubes. (not shown) disposed transversely of the unit..

'Suitable operatingfiuid, such as steam or hot water, is supplied to theelement I! through supply pipe 21 connected to the upper portion of theheader at one side, and the fluid escapes through the return pipe 22connected to the lower portion of the header at the opposite side. The

structure of element I1 forms no part of my pres- 18 cut invention andtherefore need not be shown or described in greater detail.

Water is delivered through a supply pipe 23 and is discharged into thehumidifying chamber;

I9, through a spray nozzle 24 which ejects the 80 water in a fine streamwhich impinges upon the target or plate 25 to produce a mist for'thehumidification of the air passing .through the chamber I9. The nozzle 24is preferably of the self-cleaning type. The supply of water to 26 thenozzle 24 is controlled by means of a magnetic or solenoid shut-oilvalve 26 in the supply pipe 23. In operation, the air is drawn by theblower I5 through the filter l3 into the chamber IQ for admixing withthe moisture therein, then through 30 the tempering or heating elementI! for thermally conditioning the air for comfort and for vaporizing themoisture carried thereby, and

thence through the blower to the supply outlet H for delivery to therooms. is provided forthe removal of excess water which might bedeposited within the unit I0.

The operation of the unit lllmay be flexibly controlled manually fromthe switch panel or plate "placed in a convenient location within 0 thebuilding andprovided with the switch buttons or handles 29, .30 and 3|for controlling the circuits of the several instrumentalities or devicesembodied in the unit.

' Preferably, the system is also automatically controlled by the heatresponsive circuit controlling device 32, preferably in thermal contactwith the return pipe 22 at a point thereon close to the heating elementII. The heat responsive device is of any well known type adapted to makecon- .tact and close. the circuit thereof upon rising temperature, andas the same attains a value of the order of -200'- F., accordin to theoper-' The circuit throu' {i Adrain outlet 21 35 opposite panel terminal38 of the switch 29 is connected by a lead 40 with the panel terminal 4|oi the switch 30 with which the conductor 33 is connected. The oppositepanel terminal 4| of the switch 30 is for the attachment of the lineconductor 33.

The terminal 38 is electrically connected by a bridging conductor 42with the panel terminal 43 for the switch 3|. The other terminal 43' ofthe switch II is connected by conductor 44 with one terminal of a,humidistat 45 adapted to automatically close the circuit thereof whenthe humidity drops to a predetermined value. The other terminal of thehumidistat 45 is connected by conductor 48 which the positive side ofthe solenoid valve 26 controlling the water supply and operating whenenergized to open the valve. This allows one terminal of the solenoidvalve 26 to be grounded, if so desired. The humidistat 45 may be locatedat any convenient point reflecting the humidity conditions such as inthe room, or in the air return portion i2.

In operation, when it is desired to operate the unit ll under automaticcontrol. the Switches 3! and ii are closed and the switch 28 left open.With the switches II and ii in closed position, the motor I is in serieswith the thermo-responsive device 32. and starts running as soon as thetemperature of the heating element H or i return 22 attains the desiredvalue and the circuit at the thermostat I! automatically closes. Withthe humidity control switch 3| closed, the

theme-responsive device 32 is also in series' through the parallelcircuit portion 31, connection 4!, switch 3 I and connection 44 with thehumidistat 4i and the water controlling means 28.

with the switch setting as above described, the blower II cannot operateto draw air through the unit until the temperature conditions determinedby the theme-responsive device 32 and required for desirable operationare attained. Further, the electrically operated valve 26 is also underthe control of thethermo-responsive circuit controlling device 32 andonly operates when the circuit 01' the motor it closes to supply thenozzle I4 with water tor the discharge thereof into the flowing airwithin the spray chamber '18. Such control is effective even though thehumidistat 45 is calling for more moisture. be opened the valve 28closes and the fan 'I i operates under the control oithethermostat 32-withlast control arrangement or setting the thermostat Illsshortcircuited, and the'current is supplied from the positive side ofthe line through switch 3|, conductor 40, switch", and conductor I! tothe motor I and then to the negative side I of the line for insuringcontinuous operation of the blower II. a parallel circuit is also thenIf the switch it completed through conductor, switch 3|, humidistat 45and control 26 to the negative side of the line for operation of thespray coniointly with the fan or blower. By opening switch 3|, the fanor blower I! may be operated alone without the operation of sprayingmeans 24. By opening the main control or cut-ofl switch 30 the operationof the unit can be entirely discontin- "ued, irrespective of thepositions of the other switches 28 and II.

By my invention I am able to operate the blower and spray conjointly,either under control of the thermostat 32 or not, as desired. In eithercase, the spray cannot operate unless the blower is operating, and thehumidity control circuit may be manually opened without opening thecircuit of the motor for operating the fan. The switch 30 is in seriesrelation with both the Ian operating circuit and the humidity controlcircuit, as well as with the respective switches 28 and ii locatedtherein, so that when the switch 30 is opened the operation of the motorl6 ceases and the valve 26 closes, even though the switches 28 and 3]remain closed. Irrespective of whether the motor circuit is closedthrough switch 30 or through both switches 29 and 30, the opening of theswitch 3| will interrupt the operation of the spraying means withoutdiscontinuing the operation of the motor and the blower, and the flow ofair through the system.

In my invention, the circuit connections are disposed so that the motorI and water control 28 in parallel relation may be placed either inseries relation with said thermostatic control 32 or in short-circuitedrelation thereto, and I provide means for manually controlling saidcircuits to establish eitherof said relations as desired. I am also ableby provision of a manual control in the parallel circuitportionincluding the humidity control 2' to operate the motor I and drive theblower ll without operation oi the humiditying means 24. What I claimand desire to secure by Letters Patent of the United States is:--

In air conditioning apparatus for room spaces, the combination or ahousing having an inlet and an outlet adapted to be connected to thespace to be conditioned; means providing an air passage in saidhousingconnecting the inlet and the outlet; a spray-type humidifier in saidpassage including a'spray head: a solenoid valve controlling the flow ofwater to said head; a tubular heat exchanger arranged across'saidpassage i'or heating the air leaving the humidifier; supply and returnpipes fora heating fluid connected to said heat exchanger; a blower insaid passage providing for the flow of air therethrough; an electricmotor for operating said blower; 'a thermostat responsive to thetemperature of the heating fluid at the return side of said heatexchanger; and an electrical circuit for, operating said solenoid valveand fan motor selectively by hand and in response to said thermostat andcomprising a main part including in seriesa master hand switch, saidthermostat and two branch parts in parallel, one of said branch partsincluding said motor. and the other of said ,branch parts including inseries a hand switch and said solenoid valve,'and a shunt partconnecting said master switch directly to said branch wsnrna

